We corrected a bug that prevented the intended expansion of some recursive
function calls.

We changed the handling of the primitive function ILLEGAL, which
is logically defined to be nil but which is programmed to signal an
error, so that when it is evaluated as part of a proof, it does not signal
an error. The old handling of the function prevented some guard proofs
involving THE or LETs with internal declarations.

We corrected a bug that permitted some LOCALDEFAXIOM events to slip
into certified books.

We corrected a bug that prevented the correct undoing of certain DEFPKG
forms.

Changes were made to support CMU Lisp. Pete Manolios helped with these
changes.

Changes were made to make the make files more compatible with Allegro
Common Lisp. Jun Sawada, who has been a great help with keeping ACL2
up and running at UT on various platforms, was especially helpful.
Thanks Jun.